diff --git a/SELkLockId.h b/SELkLockId.h
index 7c00c68..50c6c49 100644
--- a/SELkLockId.h
+++ b/SELkLockId.h
@@ -27,6 +27,8 @@ bool ConvertLockIdToLockId2( const std::string& sLockId, std::string& sLockId2)
 bool ConvertLockId2ToLockId( const std::string& sLockId2, std::string& sLockId) ;
 bool ConvertLockIdToScramKey( const std::string& sLockId, std::string& sScramKey) ;
 bool ConvertLockId2ToScramKey( const std::string& sLockId2, std::string& sScramKey) ;
+// Serial Number della chiave hw
+bool GetLockSN( int& nLockSN) ;
 
 //-------------------------- Constants ----------------------------------------
 // Tipo di protezione